One of the major benefits that many of you are overlooking comes in the areas that are subject to "ozone action days", like Austin, TX and other large metro areas during the summer months where lawn crews cannot legally mow before something like 10am or after 3pm due to that being the time the figure the most cars being on the road and polluting. Running a propane powered mower, a company with a fleet of these can be out there mowing whenever they want due to the low emission rating of these mowers. That is the reason that a large number of state and local bids (schools, etc) are going to these companies that can provide mowing with LPG mowers, they are not restricted to the days. And as far as having to go have tanks filled, set yourself up with a locked cage and a local company to do regular tank exchanges like they do to places that have propane tanks for retail sale.